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bodger

Bio Mass ?

Just how green is Bio Mass ? I really don't know that much about it, other than it burns renewable wood rather than fossil fuels. What else has this system got to recommend it ? Are the trees better being left and put to use helping to trap carbon emissions? If they end up being burnt, isn't any carbon that they've taken from the atmosphere simply re released ?


http://news.bbc.co.uk/1/hi/wales/wales_politics/8283923.stm


Is this just another way of polluting the planet or is it a genuine step in the right direction ?
Jamanda

The point is they use fast growing plants which take in CO2 and then release it, (carbon neutral) as a pose to just releasing it which is the case with fossil fuels.
bodger

You'll have to explain that a bit more to me I'm afraid. Embarassed Embarassed Embarassed Couldn't you argue that coal is carbon neutral but simply millions of years old ?
Jamanda

Later - have to go to work.
Treacodactyl

Coal will take carbon that's locked away and release it and there's nothing in place to lock it away again. (IIRC coal is plant matter that fell into swamps and we don't really have many similar places around the world, even if we did the process take millions of years so we would release huge amounts of CO2 and hardly any will be locked away for thousands of years).

With bio-mass such as short rotation coppice (SRC) the plant takes out CO2 as it grows and re-releases it when burn so there's no net increase in CO2. Actually there will be more CO2 taken out of the air as the roots stay behind but I expect that would balance with the CO2 used to mechanically harvest and process the wood.
bodger

Thanks for that.
So fossil fuels have already worked their magic and in an ideal world we'd leave them where they are along with the carbon that they've taken from the environment. Our aim with bio mass therefore, is not to reduce the carbon in the environment but to keep the levels that we have now, fairly static by juggling it between growing trees and using them to produce energy.

I realise that this is a rather simplistic assessment but is this more or less what bio mass is about ?
Treacodactyl

That sounds about right, I also seem to recall it being much hotter with higher CO2 concentrations when coal was formed so if we burn it all it seems logical we'd go back to similar conditions (tropical, higher sea levels, less land mass extinctions etc.)
RichardW

Burning them simply releases the Co2 that will be released when the tree dies & rots down any way.
cab

You've also got to ask how much fuel is used in planting, tending, harvesting, processing and transporting the biomass. Its not always clear cut that you're making a big carbon saving by burning biomass. Ultimately the energy density of biomass that hasn't been compressed and processed my millions of years of geology may be a lot lower than that which has (fossil fuels), so burning fossil fuels to make and move biomass may not always be quite as good an idea as you'd hope.
Jamanda

But you also have to factor in the fossil fuel you would use to extract and move the fossils fuel. I believe the coal burnt at Drax now comes from China, where as when they trailed co-burning with willow it came from Eggborough (about five miles away)
Erikht

bodger wrote:
Thanks for that.
So fossil fuels have already worked their magic and in an ideal world we'd leave them where they are along with the carbon that they've taken from the environment. Our aim with bio mass therefore, is not to reduce the carbon in the environment but to keep the levels that we have now, fairly static by juggling it between growing trees and using them to produce energy.

I realise that this is a rather simplistic assessment but is this more or less what bio mass is about ?


The carbon is supposed to return to the system, but preferably at the same time rate as it got there in the first place, slowly.
Rob R

Jamanda wrote:
But you also have to factor in the fossil fuel you would use to extract and move the fossils fuel. I believe the coal burnt at Drax now comes from China, where as when they trailed co-burning with willow it came from Eggborough (about five miles away)


That's right, it's crazy that we can't even produce our own pollution cheaper than shipping it half way around the world. Laughing

The collapse of the original biomass scheme has left many acres of willow in East Yorkshire that are now way past cutting for biomass. Like most things we do it is a question of scale- we tend to always think 'big is better', rather than the truth which is 'big is cheaper'.
vegplot

bodger wrote:
Thanks for that.
So fossil fuels have already worked their magic and in an ideal world we'd leave them where they are along with the carbon that they've taken from the environment. Our aim with bio mass therefore, is not to reduce the carbon in the environment but to keep the levels that we have now, fairly static by juggling it between growing trees and using them to produce energy.

I realise that this is a rather simplistic assessment but is this more or less what bio mass is about ?


in a nutshell yes.

coal, oil, peat etc is natures way of locking up carbon until the day the sun burns up the earth by which time it won't matter, that is until we came along.
dpack

umm
i have some cheap greenwash for sale
Ixy

Fossil fuel gets used up wayyyyy faster than it's remade. So even if biomass is less efficient, it will still be there when coal runs out. (unless by the time we've burnt all the coal, oil and gas the earth won't be able to sustain life Wink )
dpack

recon that biomass in an industrial context is greenwashing
Ixy

I'm just glad they're at least attempting it.
Rob R

Ixy wrote:
I'm just glad they're at least attempting it.


If people don't want to pay for food anymore it's better than set-aside.
arvo

The main thing to be said in its favour is it doesn't require very much in the way of investment. Just investment in the farmers growing enough of the stuff to keep the turbines running (though I'm guessing this is astronomical amounts). However it shouldn't keep us too far away from stuff like wind wave and solar where we can (mostly the two former in this country ) and before that some utter no-brainers like just giving people grants to lag their loft to Swedish standards and banning the sale of kit that has a stand-by function.

The sad truth is that I think none of the governments will get off their lazy petrol financed a***s to do anything about it until some big first world costal town gets hit by a disaster. I just hope that by the time that happens things aren't too fubar. (can I say fubar?)
vegplot

Not a believer in large scale biomass, can't think how it can be sustainable and adaptive to peoples needs.

I'm very much in favour in the small scale where 'waste' can be used (forestry thinnings etc.) for personal or local community projects.
Hairyloon

Look to the oceans...
vegplot

Hairyloon wrote:
Look to the oceans...


Drying water to burn is a bit energy intensive don't you think.
Rob R

vegplot wrote:
Hairyloon wrote:
Look to the oceans...


Drying water to burn is a bit energy intensive don't you think.


Didn't they used to burn fish in power stations?
Hairyloon

Rob R wrote:
Didn't they used to burn fish in power stations?

Only when they weren't watching the grill pan. Wink
vegplot

Rob R wrote:
vegplot wrote:
Hairyloon wrote:
Look to the oceans...


Drying water to burn is a bit energy intensive don't you think.


Didn't they used to burn fish in power stations?


All kinds of offal. Better utilised as fertiliser IMHO.
Hairyloon

vegplot wrote:
All kinds of offal. Better utilised as fertiliser IMHO.

Or animal feed.
vegplot

This is an interesting story. I wonder if we will learn from past mistakes.

Logging 'caused Nazca collapse'
vegplot

Hairyloon wrote:
vegplot wrote:
All kinds of offal. Better utilised as fertiliser IMHO.

Or animal feed.


Have we been there before with bovine CJD?
Hairyloon

vegplot wrote:
Hairyloon wrote:
vegplot wrote:
All kinds of offal. Better utilised as fertiliser IMHO.

Or animal feed.

Have we been there before with bovine CJD?

Cannibalism is generally not a good idea, nor I expect is feeding much meat to herbivores.
If your offal is too generic to tell, then feed it to something completely else (maggots?), then feed the else to something tasty.
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